It used to be that the customer was always right. In the theater, the playwright is always right. At least he gets the last word. And when you're writing thinly disguised autobiography, it's only natural to want to make yourself out to be the good guy, more sinned against than sinning. In After the Fall, Arthur Miller's scabrous self-justification for his failed marriage to Marilyn Monroe, the character of Quentin stands in for the all-knowing Miller. On the page Quentin is insufferably correct. But in the searing Muddy Waters staging of this theatrical hair shirt, John Flack's merciless portrayal of Quentin avoided so much as a smidgen of smugness. Flack took the viewer by the hand and traversed an obstacle course through Hell. Even more amazing than his unsparing performance was how effortlessly Flack was able to pull off what, up till now, has long been deemed an unplayable role.